This invention relates to an electronic camera, and more particularly to an electronic camera which can be connected to an external printer to output its data through the printer.
In addition to so-called silver salt cameras for recording an optical image of an object on a film using the photochemical reaction of silver halide, electronic cameras have come to be used widely, which convert an optical image of an object into an electrical signal to thereby electrically record the image, using the photoelectric conversion of a semiconductor represented by silicon. Among the electronic cameras, so-called digital cameras for recording a digital electric signal have come into mainstream use.
In the digital cameras, image information indicative of an object is recorded as a digital signal in a digital memory which is fixedly or detachably attached to the main body. The recorded image data is transferred from a data communication port provided at an appropriate portion of the camera main body to a universal personal computer (PC) via wire communication or radio communication using, for example, infrared rays.
Further, in the case of digital cameras having detachable memories, data can be also transferred by, for example, dismounting a card memory and reading data therein using a certain data reader.
The transferred image data can be displayed, edited or stored in a PC, or output by printing using a printer connected to the PC.
Since the digital cameras have a function as an image input device for inputting image data into the PC, the image data is processed usually in the form of a file as in the PC. Typically, data indicative of one still image corresponds to one file.
Moreover, in the digital cameras, there is additional data attached to image data. Typical additional data relates to the date and time at which an image indicated by image data is photographed (date/time data: this will often be referred to as "date"). The date/time data is output as data indicative of the date and time of photographing by a clock mechanism incorporated in the cameras.
In silver salt cameras at least before the invention of recent advanced photo systems, such a date and time have been recorded by a technique for superimposing on a film the date and time as an image (i.e. a character pattern). Record of the date and time using this technique became widespread after a "date-included picture" in which the date and time is superposed on a corner portion of the picture was put into practice. The selection of whether or not to superpose the date and time must be done immediately before photographing (i.e. exposing the film), and cannot be done afterwards.
On the other hand, since in the case of digital cameras, an image itself is converted into digital data, data on the date and time can be added to the image data, and the total data is dealt with as one image file. As a result, the date and time can be recorded without superimposing date/time data on image data. This means that whether or not a date/time character pattern should be superimposed on an image can be determined voluntarily at the time of display or printing, and also that the date/time data can be used for the management of images performed in a reproduction machine such as a camera itself or the PC.
In the actual camera, the additional data includes, as well as the date/time data, various photograph data--the numeral of each film frame, so-called comment data voluntarily input by the photographer, data on image quality such as the number of pixels or compressibility, exposure data on shutter speed, the aperture or the strobe, lens data on the distance to the object, zoom or macro, and data on white balance or the light source, photograph mode data on self-timer, automatic shooting or combination of pictures. These additional data items are employed if necessary.
Where the additional data is displayed or printed by the general PC, the display or printing can be optimized in accordance with software used in the PC. This is because the screen of the PC usually has a sufficient resolution and wide area, and hence it is not so difficult to simultaneously display thereon plural images or a print mode or an operation menu.
On the other hand, attention has recently been being paid to a method for directly printing an image (hereinafter referred to as "direct printing"), in which the camera is directly connected to the printer by a cable or radio without using a PC, and which satisfies the demand for digital cameras of users who do not have PCs.
Under the above-described circumstances of use, the users generally use an image display which is incorporated in the digital camera. In light of limitations such as size, cost, power, etc., the type of device used as the incorporated image display is limited, and a color LCD with a diagonal of about 2 inches or less is mainly used at the present stage.
To perform an operation for printing within the above-mentioned very much limited display performance (e.g. resolution, area, etc.), an easy-to-understand operation is required. Further, since the direct printing is assumed to be performed by general users other than the PC users as described above, the special knowledge of the operators or users has to be assumed to be very low, which means that a so-called foolproof system is highly requested.
In other words, the direct printing system employs special techniques basically different from the use of the PC, which relate to a user's operating method and/or a display manner of the state (e.g. the set mode) of the camera performed before the operation of the camera.
There is a reverse printing function as one function concerning the direct printing of the digital camera. The reverse printing function implies printing of a reversed image. The reversed image corresponds to a left-right-reversed image as a usual term, and a mirror image as a physical term.
Concerning the reverse print, various ends of use can be considered. In a case where an image is printed in a transfer film called, for example, "iron print", and then heat-transferred onto a T-shirt using e.g. a domestic iron, the image is reversed when transferred, and therefore reverse printing is employed to compensate the reverse transfer.
Furthermore, where a person is photographed by side looking photographing using a mirror in order to take a picture of them without making him aware of a subject situated to the side of them, a photographed image will be reversed and therefore reversal printing is used to compensate it.
Suppose that in the above-mentioned various cases, printing is done with supplementary data superimposed on an image. In this case, it should be noted that reversal printing is appropriate or inappropriate, depending upon whether character data is superimposed, or a character pattern is reversed or non-reversed. The following cases are inappropriate ones:
(1) When an image is printed on e.g. a T-shirt, it is disadvantageous in light of design if a character pattern such as a date pattern is superimposed on the image;
(2) When the date is to be printed, if the character pattern is superimposed on the image by non-reverse printing, a reversed character pattern will be printed on the T-shirt; and
(3) Where reverse printing is used to compensate a reversed image obtained by, for example, side-looking photographing using a mirror, if the character pattern is superimposed on a resultant image, the character pattern will be reversed.
If the camera is constructed such that it can perform all kinds of printing capable of dealing with the above-described cases, it is highly possible that the above-mentioned inappropriate printing will be performed, and hence it is necessary to pay special attention so as not to avoid such inappropriate printing. This may significantly degrade the operability of the direct printing system.
It is the object of the invention to provide an electronic camera capable of performing appropriate direct printing corresponding to the purpose in a simple manner without much chance of failure, in particular, to superimpose supplementary data on an image in a reversal print mode.